I'm not exactly sure if I'm using the correct terminology, but they have a switch (may be what someone earlier referred to as the SWM system) that all of the DVRs connect to via existing coax. That allows each of the DVRs to communicate with each other for the whole home DVR.

Then, like The Bad Guy was referring to, they have another device that connects to your router. Coax runs from the DIRECTV switch to the device that connects to your router. That allows all of the DVRs to connect to the Internet for updates, on demand stuff, etc.

So, to answer the original question, technically it's not wireless but you shouldn't have to run any additional cabling or anything for the most part.

DirecTV has treated me like a champ. That being said, they understand my options for HD television are numerous and want my money. I currently pay $73/month for Choice Plus (250+ channels) and free Sunday Ticket. With five other options and Google fiber moving in it's a consumer orgasm.